Experienced Senior Database Administrator, Senior Database Developer with over 20+ years of experience in PostgreSQL. Strong knowledge in designing, coding, testing and profiling PostgreSQL database in the highly loaded environment. Experienced with sharding and High-Availability (HA) techniques based on PL/Proxy, PgBouncer, Pgpool-II, repmgr, Patroni. Strong knowledge on PostgreSQL contribs (hstore, ltree, intarray, dblink, pg_trgm, pgcrypto, etc) and on internals of PostgreSQL itself. Experienced in PostgreSQL profiling tools like pg_stat_statements, pg_stat_kcache, amcheck, amcheck_next, pg_metricus, pgbadger, plpgsql_check, pganalyze and others. Good experience in PL/pgSQL, PL/SQL and ETL scripting and query optimization. • Responsible for providing 24x7 support for production PostgreSQL databases (80+ servers, 10000+ Databases, 500Tb+ data) for different cloud products (OSS/BSS, OCS, VoIP, CRM, Call Tracking, DNS) • Migrate database schema, business logic (PL/SQL to PL/pgSQL), functions, triggers, views, data from Oracle database to PostgreSQL database • Migrate PostgreSQL database schema and data from regular tables to partitioning tables (triggers, pg_partman, pg_pathman, built-in) • Migrate PostgreSQL databases from different replication systems (londiste, pglogical, streaming replication, logical replication) • Upgrade PostgreSQL databases and application tools from/to PostgreSQL versions 9.0, 9.1, 9.2, 9.3, 9.4, 9.5, 9.6, 10, 11, 12, 13, 14, 15, 16 with minimal downtime • Create a backup, recovery, disaster recovery, fault tolerance, RPO/RTO plan for databases in co-location and multi-datacenters environment (pg_probackup, barman, pgBackRest, WAL-G, pg_basebackup, PITR, ceph, repmgr, PgBouncer) • Create monitoring center, new monitoring metrics, log analysis of PostgreSQL databases (Zabbix, Grafana, Prometheus, mamonsu, pgbadger, powa) • Create a Data Warehouse based on Greenplum Database, ClickHouse, Citus and PostgreSQL materialized views and migrate OLAP data to it • Create a Change Data Capture (CDC) system (pgoutput, decoderbufs, wal2json, Debezium, Kafka) to capture, track and replicate changes for processing across different systems and applications (Auditing, Compliance, Data Integration & Synchronization, Real-time Analytics, Event-Driven Architecture, Fraud Detection, ETL) • Create and maintain staging database environments as well as hot standby databases (ansible, barman, repmgr, patroni, various scripts) • Stress and fuzz tests of application releases in development cycle, PostgreSQL versions and new hardware (pgbench, Tsung, JMeter, various scripts) • Provide technical resolution to PostgreSQL database related problems (pg_stat_statements, pg_stat_kcache, amcheck, amcheck_next, pg_metricus, pg_repack, execution plan analysis, plpgsql_check, pganalyze) • Design, build and manage the ELK (Elasticsearch, Logstash, Kibana) and Grafana Loki cluster for centralized PostgreSQL logging and search functionalities • Maintain very large legacy code written in PL/pgSQL, develop database architecture, regular review a new code • Create a DBA team. Recruit, hire and train new employees